New Zealander Shane van Gisbergen has posted the fastest time in Friday practice for this weekend's V8 Supercars event in Darwin.

Van Gisbergen clocked a time of 1:09.3436 to finish just ahead of reigning champion Jamie Whincup

Whincup, who is fourth in the standings going into this weekend's event, clocked a best lap of 1:09.6227. The Holden driver hasn't won a race since March and will be eager for a big weekend as he aims to get his title defence back on track.

Holden's James Courtney was the third fastest, clocking a quickest lap of 1:09.8988 in hot and humid conditions at Hidden Valley Raceway.

Championship leader Mark Winterbottom was the 10th fastest on the day with his nearest rival, Craig Lowndes, just pipping him on the time sheets.

Lowndes, who turns 40 on Saturday, clocked a 1:10.5354 best lap while Winterbottom's best was a 1:10.5610.

Earlier in the day, Holden's Fabian Coulthard topped the timesheets in practice one before Nissan's James Moffat was fastest in the day's second session.

Saturday's action features two 100km races with a 200km race on Sunday.